Electric control mechanism.



No. 851,633. PATENTED APR. 23, 1907.

' P. SYNNESTVEDT.

ELECTRIC CONTROL MECHANISM.

APPLICATION FILED AUG.30.1904.

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UNIT ED STA .ss

PAUL sYNNEsirvrn'r, or

NEs'rvEn'r Miner" CORPORTEON or critic GQllTR Specification of LettersPatent.

PATENT OFFICE IWEZCHANlSM.

Patented April 23, 1907.

Application and August 20,1904... seimi in. 222,711.

To It who/i1, it 777/6201] concern:

Be it known tl at I, PAUL SYN'NESTVEDT, a citizen the U States,resililing st Pitts burg, in the county oi Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inElectric-Control lllechanisin, of which the following is especification.

The primary object of this present invention is to secure it perfectbalance in the magnetic field of z: lcl/Jliilfl having a plurality ofcominutetcd licld windings, as where the speed control of a motor isobtained by vsrietions in the iield windings, as for example where thewindings are so connected to a controller and manipulated in theoperation of such controller as to place them first in series and thenin series multiple and then in multiple connection.

' In order that the invention. may be better u derstood .i will describethe some in connection with the accompanying drawing, whereiiji Figure lis a, diagrammatic representation showing the controller employedtogether with the diagrammatic indications of the several coils employedon the motor;

lligure is e diagrunnnatic view representing; the preferable form ofwinding which i employ on the motor;

Figure 3 is e diagram showing the COHZIQO tions of the several fieldwindings in wliet is called the first forward position Figure 4indicates the connections of the second forward positions;

Figure S the connections in the third ion ward position, and

Figurefi the connections or the windings i n the fourth forwardposition.

Referring first to Fl9'll 1'2 it will be seen that l have therein inditor ofthe series type having two brush connections, and each pole woundprei' i l with adouble strand. of wire laid on the pole parallel so thatthe entire iield contains 5 coils, each coil two separate terminals,which, as indicated on Figure 1, are

carried with the brush leads and one battery lead to fixed contacts onthe controller numbored respectively from 1 to 19 inclusive in e fourposition'control mechanism.

The 8 windin s oil the fields are indicated Separately one shove anotherin the lower po tion of the diagram in Figure 1, the connections to theends of the Si'tHlB being so made that the current will enter on theleft side and pass out of the windings on the right side as indicated inthe disgnni, so that the C(Miliilffid from one to eight inclusive willall carry current outward from the controller as inc-licated'by thearrows in Figure 1 while the contacts 12 to 19 wil be the returncontacts .VllfilCfI'Oll'l the current ll pass to the contact surfaces onthe barrel of the controller.

The several lieldrwindings ere merited in Figure .l, ll, A", (these twobeing the windlugs on pole A), B B-, (these two liming the windings onpole ll), C f), (the windings on pole and D D'-, (the windings on polel, end on Figure 2 the terminals of the several windings shown aremarked with the respective contact numbers to which they ere connectedto the controller. The errows on Figure 2 indicate the direction ofcurrent produced by the arrangement of Figure 1, with. the motorconnections as marked and, as will be observed by careful examination ofthe windings indicated in l igure 2, such direction of current willproduce the requisite opposite polarity of adjacent poles necessary tothe proper operation of the motor.

The battery diagramineticully iiidic ted all E'an l the commutator at.F, it v be observe that one end of the battery, that the positiveconnection, leads to Contact No. i o'l'- the controller, as an extracontact is not necessary for that, while the other end lends to ceiiitsi9, while the brush leads of the t l 0. commutator are connected tocontacts Nos. and 31 respectively, as clearly shown in the diag am oi; l

v new to the operation of the controlling mechanism considering theforward positions, and having special reference to Figure 1 "l Figures 3to 6 inclusive, it will re seen l; at when the barrel of the controllerCK "iteining the movable contacts numbered respectively 21 to 49, isturned to the position nzerked ilrst forward position, (Fig. 1) thelower edge or extremity of thecontoct 21 will register "with the linedcontact 1, end'so all. along the line permitting the current to flowfrom the battery by contact 1, down through the field coil A and back bycontact 19 where is taken by movable contact and wire connection 51 tomovable contact 2; thence by fixed contact 3 through field winding B andback byfixe i contact 17 and movab? contact 37 and wire 53 to movablecontact and fixed contact and so on aroun- H" e circuit, it beingllJSQI'VGtl th at the curren tin this position tr;.ta'el series throughone coil on each pole ail around the fietl and hen is returned by meansof the wire :3? on the barrel of the controller and the contacts 22 and2 so as to be carried in series through the remain; Jig coil on eachpole making another circuit of the fields. n this posit" 1). thereforeall of the field winding is in so; 18S, and. the field winding in turnis inseries with thearmature, and all parts of the motor must take ofcourse the same flow of current, as any break in the circuit anywherewill s"( p the flow of currentaltogether. With all of the windings as inthis position, in series, it is therefore 11mm terial what the order isin which the cin'rent orters or flows through. them, but it will be seenon exanc' ation of the flo'w of current indicated in Figure 4, which isthe second'forward position, that it now becomes of importance since thefield is cut in half as it were all the way around, that is, it isarranged in series parallel, each'of the parallel strands embracing inturn all four poles, and therefore by the disposition of the severalcontacts and windings shown I have 'oduced a condition in-wlnch thecurrent in the' second position flows in parallel by adjacent windings,all around the motor, each eries be? 1g independent of the other series,th: current finally uniting again and passing to the brush contacts. Theobject of this is to balance the circuit on the poles so that in thisposition (the 2nd) ii there should be a defective contact on any of thefield conne tions, as for example. the connection marked 2, produ ing aluced flow l'curr'ent, such reduced flow ()1. surrent through thewinding connectedwith that COHLQ that is the winding marked A would notonly be balrnced by a correspond ing reduction in the urrent through theopposite v inding which would be the winding C of the pole U, which isoppc site to the pole A, but would also in this (2nd) position'sinii-'larly afiect all four peter-In other words an open circuit in the fieldwherever it may occur will in this position have like efiect all aroundthe motor. It will also appear that in the balancing effect thusproduced the number of poles is immaterial. Thus for any reduction inthe fiov: of current in any portion of the field winding a correspondingreduction is made in other parts of the field and if the circuit sho ldbe broken altogether on contact No. 2 the result would be to cut outaltogcthei e half the windings all aroir'd the field and the motor wouldstill run in a balances field, with all poles active, but moreresistance in the windings.

course of. accc int of the nature of the commutation in the secondposition any break of that character in any one of the field contactswill cut out .one half of the field, the half being comnosed of a halfwind-' ing on each pole, no matter wher the break may occur. Not onlydoes this arrange- ,ment operate in the manner indicated in case of atotal stoppage of flow in an; portion of the field windings, but it willcompensate as suggested above where there is only partial iveco'ntaciwhich is you not all .gether open circui'ted or from a difference in theamount of wire or the carrying capac-t of the wire on any particularcoil, in Whic 1 case oppositely disposed coils or windings will takejust the corresponding amount of current so as to balance up the motor.

Observing the arrangement of the windings in Figure 5 it will be seenthat each half winding that is each separate coil on each fieldisarranged so as to be in series inde pendenily with its correspomling halcoil on the opposite pole, so the if a half of a com "plete fieldwinding on one pole is cut out, then a corresponding half or single coilwill cut out on the opposite pole (see Figure 5). This it will be observed will be true no matter which of the windings may be cut out orwhether it be on poles A. B. C. or

Of course so far as the fourth position in dicated in Figure 6 isconcerned the utting out of any one of the windings will unbalance thefield to a small extent, but this is not so material there because thereare eight conductors parallel in that position and the effect is not sopronounced as it has been found by experiment to be in the case of 'ullGother positions, as for example in the second and third position, whereaccording to other windings which have been tried by me it has been 'FL'und that if a had contact develops on a controller so as to cut out onecoil, unless an opposite coii also cuts out the unbalance produce in thefield will cause the motor to run hot in the bearing and reduce theefiiciency very mz erially thereby interfering with the successfuloperation of the machine. drawings, I have found by careful experimentthat as stated therr will be a perfect balance of the field under allconditions of service, even although one or more of-the contacts beentirel open-circuited', and with such Winding t e machine will continueto run without heating at the bearings or other detrimentalresults (savesome slight loss in efliciency) regardless of .such disadvantageousconditions. Y

Another thing to be observed in connection with the arrangement of thecontact surfaces on the controller, as shown in the drawing is that theprincipal leads, that is those which at all times carry the entirecurrent,

which are the battery leads and the two flow, as will result, sometimesfrom a defect.

IIO

With the windings shown on the brush leads, are so disposed that theyare constantly, in contact when the machine is running in for'ward'speedregardless of changes from one position to another, in other words thecontact parts on the movablepart of the controller marked 21, 2930, and31, 32, have their widest portions so disposed that they bear on thefixed terminals leading to the battery connect-ions and to the brushes,whereby the breaking which occurs in traveling from one position on thecontroller to another all takes place on the field connections, and asthere are, when heavy cur-- rent is flowing especially, a number ofthese field connections the are ]S distributed and the detrimentaleiiect thereof very largely done away with; I a 1 As a means foraffording a' return circuit from the contacts Nos. 46,47, 48 and 49 tothe other contacts on theother end of the controller with which theseare connected, I

have provided a number of short wire connections marked 50 which carrythe current back tothe contacts'34 and 37 inclusive and thus utilize thereturn wires from the latter contacts to the other end of the controllerand this avoids the necessity of providing a duplicate set of returnwires extending clear a to the other end of the controller; So far asconcerns the operationof'the mechanism in the back up, or reverseposition, it is of the commutation of a commutated field, that thecurrent when it flows in series multiple through the windings thereofwill flow through adjacent windings in multiple, and such windings willbe connected individually or separately in series with correspondingoppositely disposed windings, whereby to maintain at all times a perfectbalance in the magnetic field. It will be seen that if, as ined inFigure 5, after the current has flown in multiple through the fourwindings shown at the left of that figure the terminals of said windingsshould be connected together by a single conductor and that conductorthen taken over and connected in multiple in turn with the terminals ofthe four windings at the right of the figure the effect sought would bedestroyed because in case any one or more ofthe windings in multiplewere cut out it would not produce any corresponding effect at all on anyopposite winding.

Having thus described my invention and illustrated its use, what I claimas new and desire to secure by Letters Patent, is:

-11 An improvement in electric controlling mechanism comprising incombination, a magnetic field provided with a plurality of separatewindings, such windings being op positely disposed on said field, andmeans for connecting said windings in series and for changing saidconnections'to multiple so that the circuit in series multiple positionwill flow through oppositely disposed windings in series individually,whereby to produce a balance of said fields, substantially as described.

2. An improvement in electric controlling mechanism comprising incombination a plurality of magnetic poles, a plurality of wind-.

ings on each pole and means for commutating said windings wherebyadjacent windings on one pole may be put in multiple circuit and eachsaid winding in separate series connection with an opposite winding,substantially as described.

3. In combination with a motor having opposing poles and multipleparallel windings vices adapted to vary the number of windings throughwhich the current passes successively and at the same time maintain thewindings of opposing poles in 561165, substantially as described Intestimony whereof I have hereunto set my hand in the presence of the twosubscribing witnesses.

PAUL SYNNESTVEDT.

In the presence of HERMANX Lncnttns. C. K. HICKS.

for each pole, of circuit controlling de-

